In radio location, many radio frequency (RF) techniques may be used to determine locations of objects. Of these techniques, differential interferometry is a technique that is commonly used in many RF location applications. Several of the applications of differential interferometry are based on radar technology, in which signals (e.g., microwaves, etc.) are transmitted by a single transmitter that also functions as a receiver that listens for the signals that bounce back (a.k.a. “backscatter”) to determine object locations. For instance, ultra-wide-band radar relies greatly on differential interferometry. The transmitter of the ultra-wide-band radar uses a large energy burst to generate a strong signal. The ultra-wide-band radar would then implement a wideband receiver to listen to the response and measure the exact time it takes the response to return to the radar device.
The traditional RF devices, like the ultra-wide-band radar, implementing differential interferometry can include very complex architectures, in that, they require expensive, bulky, and often high-power consuming components. Additionally, these traditional RF devices require high speed clocks to measure actual phase differentials with very precise timing. Consequently, these RF devices have very good crystal and highly sensitive signal processing circuitry or devices to process the measurements obtained by a receiver.
Moreover, because these traditional RF devices are complex in architecture and require significant energy resources to operate, they are not suitable for more constrained applications (e.g., in geographically remote locations, in locations where GPS or similar services are unavailable, such as indoors or underground, or among low-power devices that need to be autonomous in order to function properly).
Accordingly, there is a need in the radio location field for low-power and accurate techniques and systems for locating devices and/or objects and specifically, for locating devices and/or objects in constrained applications. The below-described embodiments of the present application provide such advanced radio location technique and systems.